Seventy years ago, just as penicillin was starting to prove its value in treating infections during the second world war, researchers were already warning about the dangers of future resistance to antibiotics. A new battle against such lethal microbes now needs to begin. Each year, hospital-acquired infections such as MRSA kill more than 25,000 people in Europe alone. Migration and medical tourism are intensifying the spread of such risks. The response of governments, healthcare workers and drug companies alike has been disappointingly weak. One problem is the overuse of antibiotics, which are easily and cheaply available, often without a prescription. They are given too freely to humans and animals alike, and often taken for fewer days than required, promoting resistance. Another concern is poor hygiene control, including basic cleaning in hospitals, hand-washing, and the screening of patients who often carry MRSA with them before admission. They risk infecting others if not temporarily isolated and treated appropriately.